α2,6-Sialylation Is Upregulated in Severe COVID-19, Implicating the Complement Cascade

Better understanding of the molecular mechanisms underlying COVID-19 severity is desperately needed in current times. Although hyper-inflammation drives severe COVID-19, precise mechanisms triggering this cascade and what role glycosylation might play therein are unknown. Here we report the first high-throughput glycomic analysis of COVID-19 plasma samples and autopsy tissues. We find that α2,6-sialylation is upregulated in the plasma of patients with severe COVID-19 and in autopsied lung tissue. This glycan motif is enriched on members of the complement cascade (e.g., C5, C9), which show higher levels of sialylation in severe COVID-19. In the lung tissue, we observe increased complement deposition, associated with elevated α2,6-sialylation levels, corresponding to elevated markers of poor prognosis (IL-6) and fibrotic response. We also observe upregulation of the α2,6-sialylation enzyme ST6GAL1 in patients who succumbed to COVID-19. Our work identifies a heretofore undescribed relationship between sialylation and complement in severe COVID-19, potentially informing future therapeutic development.

Exercise-induced engagement of the IL-15/IL-15Rα axis promotes anti-tumor immunity in pancreatic cancer

Aerobic exercise is associated with decreased cancer incidence and cancer-associated mortality. However, little is known about the effects of exercise on pancreatic ductal adenocarcinoma (PDA), a disease for which current therapeutic options are limited. Herein, we show that aerobic exercise reduces PDA tumor growth, by modulating systemic and intra-tumoral immunity. Mechanistically, exercise promotes immune mobilization and accumulation of tumor-infiltrating IL15Rα+ CD8 T cells, which are responsible for the tumor-protective effects. In clinical samples, an exercise-dependent increase of intra-tumoral CD8 T cells is also observed. Underscoring the translational potential of the interleukin (IL)-15/IL-15Rα axis, IL-15 super-agonist (NIZ985) treatment attenuates tumor growth, prolongs survival, and enhances sensitivity to chemotherapy. Finally, exercise or NIZ985 both sensitize pancreatic tumors to αPD-1, with improved anti-tumor and survival benefits. Collectively, our findings highlight the therapeutic potential of an exercise-oncology axis and identify IL-15 activation as a promising treatment strategy for this deadly disease.

Abstract 6142: Gain-of-function p53R172H mutation drives accumulation of neutrophils in the pancreatic tumor microenvironment promoting resistance to immunotherapy

The immune microenvironment plays a critical role in cancer development, progression and resistance to therapy. Specific tumor genotypes can profoundly influence the composition of the immune microenvironment. After oncogenic KRAS, TP53 is the most frequently mutated gene in pancreatic ductal adenocarcinoma (PDAC). KRASG12D mutations in tumor cells are known to modify the immune landscape of PDAC, however the immune effects of neomorphic TP53 mutations have not been defined. Focusing on the most common neomorphic TP53 mutation in human PDAC, we sought to evaluate the non-cell-autonomous role of gain-of-function mutant Trp53R172H in modulating the immune microenvironment of pancreatic tumors by using KrasG12D-mutated mouse pancreatic ductal epithelial cells (PDEC) genetically engineered to express the Trp53R172H gain-of-function. Orthotopically implanted tumors derived from CRISPR-generated KrasG12D/+;Trp53R172H/+ PDEC had a distinct immune profile in comparison to KrasG12D/+;Trp53+/+ tumors, characterized by an influx of intratumoral CD11b+Ly6G+ neutrophils and concomitant decreases in CD3+ T cells, CD8+ T cells, and CD4+ T helper 1 (Th1) cells. Analysis of publicly available human PDAC cohorts revealed enrichment of genes in neutrophil-related pathways in TP53-mutated tumors. Knockdown of CXCL2, a neutrophil chemoattractant, in the tumor epithelial compartment of CRISPR KrasG12D/+;Trp53R172H/+ PDEC tumors reversed the neutrophil phenotype. Depleting neutrophils in mice bearing CRISPR KrasG12D/+;Trp53R172H/+ PDEC tumors augmented sensitivity to combined CD40 immunotherapy and chemotherapy. Collectively, these data link gain-of-function mutant Trp53R172H to the presence of intratumoral neutrophils in pancreatic cancer and suggests that tumor genotypes could inform patient selection for immunotherapy.

Citation Format: Despina Siolas, Emily Vucic, Emma Kurz, Cristina Hajdu, Dafna Bar-Sagi. Gain-of-function p53R172H mutation drives accumulation of neutrophils in the pancreatic tumor microenvironment promoting resistance to immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6142.

α2,6-Sialylation is Upregulated in Severe COVID-19 Implicating the Complement Cascade

Better understanding of the mechanisms of COVID-19 severity is desperately needed in current times. Although hyper-inflammation drives severe COVID-19, precise mechanisms triggering this cascade and what role glycosylation might play therein is unknown. Here we report the first high-throughput glycomic analysis of COVID-19 plasma samples and autopsy tissues. We find α2,6-sialylation is upregulated in plasma of patients with severe COVID-19 and in the lung. This glycan motif is enriched on members of the complement cascade, which show higher levels of sialylation in severe COVID-19. In the lung tissue, we observe increased complement deposition, associated with elevated α2,6-sialylation levels, corresponding to elevated markers of poor prognosis (IL-6) and fibrotic response. We also observe upregulation of the α2,6-sialylation enzyme ST6GAL1 in patients who succumbed to COVID-19. Our work identifies a heretofore undescribed relationship between sialylation and complement in severe COVID-19, potentially informing future therapeutic development.

Integrated Systems Analysis of the Murine and Human Pancreatic Cancer Glycomes Reveals a Tumor-Promoting Role for ST6GAL1

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer death in the United States. Glycans, such as carbohydrate antigen 19-9, are biomarkers of PDAC and are emerging as important modulators of cancer phenotypes. Herein, we used a systems-based approach integrating glycomic analysis of the well-established KC mouse, which models early events in transformation, and analysis of samples from human pancreatic cancer patients to identify glycans with potential roles in cancer formation. We observed both common and distinct patterns of glycosylation in pancreatic cancer across species. Common alterations included increased levels of α-2,3-sialic acid and α-2,6-sialic acid, bisecting GlcNAc and poly-N-acetyllactosamine. However, core fucose, which was increased in human PDAC, was not seen in the mouse, indicating that not all human glycomic changes are observed in the KC mouse model. In silico analysis of bulk and single-cell sequencing data identified ST6 beta-galactoside alpha-2,6-sialyltransferase 1, which underlies α-2,6-sialic acid, as overexpressed in human PDAC, concordant with histological data showing higher levels of this enzyme at the earliest stages. To test whether ST6 beta-galactoside alpha-2,6-sialyltransferase 1 promotes pancreatic cancer, we created a novel mouse in which a pancreas-specific genetic deletion of this enzyme overlays the KC mouse model. The analysis of our new model showed delayed cancer formation and a significant reduction in fibrosis. Our results highlight the importance of a strategic systems approach to identifying glycans whose functions can be modeled in mouse, a crucial step in the development of therapeutics targeting glycosylation in pancreatic cancer.

Gain-of-function p53R172H mutation drives accumulation of neutrophils in pancreatic tumors, promoting resistance to immunotherapy

Tumor genotype can influence the immune microenvironment, which plays a critical role in cancer development and therapy resistance. However, the immune effects of gain-of-function Trp53 mutations have not been defined in pancreatic cancer. We compare the immune profiles generated by KrasG12D-mutated mouse pancreatic ductal epithelial cells (PDECs) engineered genetically to express the Trp53R172H mutation with their p53 wild-type control. KrasG12D/+;Trp53R172H/+ tumors have a distinct immune profile characterized by an influx of CD11b+Ly6G+ neutrophils and concomitant decreases in CD3+ T cells, CD8+ T cells, and CD4+ T helper 1 cells. Knockdown of CXCL2, a neutrophil chemokine, in the tumor epithelial compartment of CRISPR KrasG12D/+;Trp53R172H/+ PDEC tumors reverses the neutrophil phenotype. Neutrophil depletion of mice bearing CRISPR KrasG12D/+;Trp53R172H/+ tumors augments sensitivity to combined CD40 immunotherapy and chemotherapy. These data link Trp53R172H to the presence of intratumoral neutrophils in pancreatic cancer and suggest that tumor genotypes could inform selection of affected individuals for immunotherapy.

Abstract LT005: Tumor-intrinsic gain of function p53R172H mutation drives accumulation of neutrophils in the pancreatic tumor microenvironment that promotes resistance to immunotherapy

KRASG12D mutations in tumor cells can modify the immune microenvironment of pancreatic ductal adenocarcinoma (PDAC), though the effects of secondary genetic alterations have been unexplored. After oncogenic KRAS, TP53 is the most frequently mutated gene in PDAC, however the immune effects of neomorphic TP53 mutations have not been defined. We sought to evaluate the non-cell-autonomous role of mutant p53 in modulating the immune microenvironment of pancreatic cancer by comparing the immune profiles generated by KrasG12D-mutated mouse pancreatic ductal epithelial cells (PDEC) genetically engineered to express the Trp53R172H gain-of-function mutation to their p53 wildtype control. We found orthotopically implanted tumors derived from KrasG12D;Trp53R172H PDEC had a distinct immune profile in comparison to KrasG12D/+;Trp53+/+ tumors, characterized by an influx of intratumoral CD11b+Ly6G+ neutrophils and concomitant decreases in CD3+ T cells, CD8+ T cells, and CD4+ T helper 1 (Th1) cells. Analysis of publicly available human PDAC cohorts revealed enrichment of genes in neutrophil-related pathways in TP53-mutated tumors. Knockdown of CXCL2, a neutrophil chemoattractant, in the tumor epithelial compartment of KrasG12D;Trp53R172H PDEC tumors reversed the neutrophil phenotype. Depleting neutrophils in mice bearing KrasG12D;Trp53R172H PDEC tumors augmented sensitivity to combined CD40 immunotherapy and chemotherapy. Collectively, these data link mutant p53 to the presence of intratumoral neutrophils in pancreatic cancer and suggests that tumor genotypes could inform patient selection for immunotherapy.

Citation Format: Despina Siolas, Emily Vucic, Emma Kurz, Cristina Hajdu, Dafna Bar-Sagi. Tumor-intrinsic gain of function p53R172H mutation drives accumulation of neutrophils in the pancreatic tumor microenvironment that promotes resistance to immunotherapy [abstract]. In: Proceedings of the AACR Virtual Special Conference on the Evolving Tumor Microenvironment in Cancer Progression: Mechanisms and Emerging Therapeutic Opportunities; in association with the Tumor Microenvironment (TME) Working Group; 2021 Jan 11-12. Philadelphia (PA): AACR; Cancer Res 2021;81(5 Suppl):Abstract nr LT005.

Abstract PR-005: Tumor intrinsic p53 mutation drives accumulation of neutrophils in the pancreatic tumor microenvironment promoting resistance to immunotherapy

Intratumoral genetic alterations can cause remodeling of local immune cell populations through distinct cellular mechanisms. After oncogenic KRAS, TP53 is the gene most frequently mutated in pancreatic ductal adenocarcinoma (PDAC). These mutations in TP53 are neomorphic and confer phenotypes distinct from those due to homozygous TP53 deletion. We sought to evaluate the non-cell-autonomous role of mutant p53 protein in the immune microenvironment by studying KrasG12D-mutated mouse pancreatic ductal epithelial cells (PDEC) engineered using CRISPR/Cas gene editing to express the Trp53R172H gain-of-function mutation. We found distinct immune profiles associated with orthotopically implanted tumors derived from KrasG12D;Trp53R172H PDEC, characterized by an influx of intratumoral CD11b+Ly6G+ neutrophils and concomitant decreases in CD3+ T cells, CD8+ T cells, and CD4+ T helper 1 (Th1) cells. Analysis of publicly available human PDAC cohorts revealed enrichment of genes in neutrophil-related pathways in TP53-mutated tumors. Knockdown of CXCL2, a neutrophil chemoattractant, in the tumor epithelial compartment of KrasG12D;Trp53R172H PDEC tumors reversed the neutrophil phenotype. Depleting neutrophils in mice bearing KrasG12D;Trp53R172H PDEC tumors augmented sensitivity to combined CD40 immunotherapy and chemotherapy. Collectively, these data link mutant p53 to the presence of intratumoral neutrophils in pancreatic cancer and suggests that tumor genotypes could inform patient selection for immunotherapy.

Citation Format: Despina Siolas, Emily Vucic, Emma Kurz, Cristina Hajdu, Dafna Bar-Sagi. Tumor intrinsic p53 mutation drives accumulation of neutrophils in the pancreatic tumor microenvironment promoting resistance to immunotherapy [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2020 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2020;80(22 Suppl):Abstract nr PR-005.

Epigenetic silencing of the ubiquitin ligase subunit FBXL7 impairs c-SRC degradation and promotes epithelial-to-mesenchymal transition and metastasis

Epigenetic plasticity is a pivotal factor that drives metastasis. Here, we show that the promoter of the gene that encodes the ubiquitin ligase subunit FBXL7 is hypermethylated in advanced prostate and pancreatic cancers, correlating with decreased FBXL7 mRNA and protein levels. Low FBXL7 mRNA levels are predictive of poor survival in patients with pancreatic and prostatic cancers. FBXL7 mediates the ubiquitylation and proteasomal degradation of active c-SRC after its phosphorylation at Ser 104. The DNA-demethylating agent decitabine recovers FBXL7 expression and limits epithelial-to-mesenchymal transition and cell invasion in a c-SRC-dependent manner. In vivo, FBXL7-depleted cancer cells form tumours with a high metastatic burden. Silencing of c-SRC or treatment with the c-SRC inhibitor dasatinib together with FBXL7 depletion prevents metastases. Furthermore, decitabine reduces metastases derived from prostate and pancreatic cancer cells in a FBXL7-dependent manner. Collectively, this research implicates FBXL7 as a metastasis-suppressor gene and suggests therapeutic strategies to counteract metastatic dissemination of pancreatic and prostatic cancer cells.

γδ T Cells Promote Steatohepatitis by Orchestrating Innate and Adaptive Immune Programming

BACKGROUND AND AIMS

The recruitment and activation of inflammatory cells in the liver delineates the transition from hepatic steatosis to steatohepatitis (SH).

APPROACH AND RESULTS

We found that in SH, γδT cells are recruited to the liver by C-C chemokine receptor (CCR) 2, CCR5, and nucleotide-binding oligomerization domain-containing protein 2 signaling and are skewed toward an interleukin (IL)-17A⁺ phenotype in an inducible costimulator (ICOS)/ICOS ligand-dependent manner. γδT cells exhibit a distinct Vγ4⁺ , PD1⁺ , Ly6C⁺ CD44⁺ phenotype in SH. Moreover, γδT cells up-regulate both CD1d, which is necessary for lipid-based antigens presentation, and the free fatty acid receptor, CD36. γδT cells are stimulated to express IL-17A by palmitic acid and CD1d ligation. Deletion, depletion, and targeted interruption of γδT cell recruitment protects against diet-induced SH and accelerates disease resolution.

CONCLUSIONS

We demonstrate that hepatic γδT cells exacerbate SH, independent of IL-17 expression, by mitigating conventional CD4⁺ T-cell expansion and modulating their inflammatory program by CD1d-dependent vascular endothelial growth factor expression.

P03.04 Signaling questions assessing brain tumor patients’ distress in clinical routine - a feasibility study

BACKGROUND

Approximately 20%-35% of patients with intracranial tumors show depressive symptoms and distress. Assessment in these patients remains challenging due to cognitive and/or neurological deficits. We developed 3 signaling questions in order to assess patients during patient-doctor consultation. The aim is to implement them in clinical routine and to compare the results with patient reported outcome measures (PROMs) along disease trajectory.

MATERIAL AND METHODS

Patients were prospectively examined in a structured interview applying the 3 following questions: 1),Has your mood worsened? (I)”; 2),Are you strained by physical changes? (II)”; 3),Has your faculty of thought decreased? (III)”. Simultaneously, patients filled in the Distress Thermometer (DT) and the EORTC QLQ-C30 + BN20. The first patient group was assessed twice pre- and postoperatively in the very early disease trajectory (A), the second patient group once in the outpatient setting during adjuvant therapy or follow-up (B). The results of the 3 signaling questions were compared to the results of the PROMs.

RESULTS

A total of n=62 patients gave informed consent and n= 61 were assessed so far. In general, the signaling questions were feasible to answer for all patients. However, patients frequently needed more detailed examples for symptoms emphasizing the intention of the question.

In group A (n= 20), patients had a mean age of 59 years, n= 12 (60%) were male. Main diagnoses were glioblastomas, meningiomas and metastases. The results of the signaling questions did not reflect the screening by DT: N= 11 (55%) reported that their mood has worsened (I) prior to the operation, which then improved to n= 5 (31%) patients afterwards. The same applied to physical changes (II, 10 (50%) vs. 7 (44%), as well as lower cognition (III, 7 (35%) vs. 4 (25%) respectively). In contrast, mean DT (5.7 vs. 6 after) as well as the mean number of positive responses to the problem lists on the DT was similar pre- and postoperatively (8.7 pre-op vs. 9.4 post-op).

Group B, (n= 41) consisted of patients harboring malignant gliomas, n= 27 (66%) were male. Patients had a mean DT score = 6.8, n= 22 (53%) named a worse mood (I), n= 23 (56%) patients reported physical changes (II) and n= 22 (54%) patients reported lower cognition (III), global health scale (GHS) according to the EORTC instrument was 60 (0–100). The majority of patients with a DT ≥6 also reported strain in the signaling questions and had a lower mean GHS = 54,8. DT ≥ 6 was linked to worse mood (I, Fishers exact, p=0.02).

CONCLUSION

According to our preliminary data, the signaling questions seem to be more useful in the outpatient setting in glioma patients than perioperatively. “Has your mood worsened” was associated with higher burden according to DT. Screening in brain tumor patients could probably complemented by direct questions in order to avoid missing patients who are not able to fill in questionnaires.

Innate αβ T Cells Mediate Antitumor Immunity by Orchestrating Immunogenic Macrophage Programming

Unconventional T-lymphocyte populations are emerging as important regulators of tumor immunity. Despite this, the role of TCRαβ⁺CD4^-CD8^-NK1.1^- innate αβ T cells (iαβT) in pancreatic ductal adenocarcinoma (PDA) has not been explored. We found that iαβTs represent ∼10% of T lymphocytes infiltrating PDA in mice and humans. Intratumoral iαβTs express a distinct T-cell receptor repertoire and profoundly immunogenic phenotype compared with their peripheral counterparts and conventional lymphocytes. iαβTs comprised ∼75% of the total intratumoral IL17⁺ cells. Moreover, iαβT-cell adoptive transfer is protective in both murine models of PDA and human organotypic systems. We show that iαβT cells induce a CCR5-dependent immunogenic macrophage reprogramming, thereby enabling marked CD4⁺ and CD8⁺ T-cell expansion/activation and tumor protection. Collectively, iαβTs govern fundamental intratumoral cross-talk between innate and adaptive immune populations and are attractive therapeutic targets. SIGNIFICANCE: We found that iαβTs are a profoundly activated T-cell subset in PDA that slow tumor growth in murine and human models of disease. iαβTs induce a CCR5-dependent immunogenic tumor-associated macrophage program, T-cell activation and expansion, and should be considered as novel targets for immunotherapy.See related commentary by Banerjee et al., p. 1164.This article is highlighted in the In This Issue feature, p. 1143.

Breast Density in a Contemporary Cohort of Women With Ductal Carcinoma In Situ (DCIS)

BACKGROUND

Mammographic breast density (MBD) is an independent risk factor for breast cancer. Information regarding the relationship of MBD and breast cancer biology in women with ductal carcinoma in situ (DCIS) is currently lacking. This study aimed to examine the clinicopathologic characteristics of DCIS in women stratified by MBD.

METHODS

A retrospective review was performed to identify women with pure DCIS who underwent preoperative mammography between 2010 and 2018. Clinicopathologic and demographic data were collected. For the purpose of analysis, MBD was categorized as "non-dense" (Breast Imaging-Reporting and Data System [BI-RADS] density categories A and B) or "dense" (BI-RADS C and D) according to its identification in radiology reports.

RESULTS

Of 3227 patients with a breast cancer diagnosis enrolled in the institutional Breast Cancer Database during the study period, 658 (20%) had pure DCIS. Of these 658 patients, 42% had non-dense breasts, and 58% had dense breasts. Most lesions were non-palpable (92%) and detected by mammography (84%). Patients with dense breasts were more likely to be younger at the time of diagnosis (p < 0.001), premenopausal (p < 0.001), and Asian (p = 0.018), and to have higher-grade disease (p = 0.006; Table 2). Family history, BRCA status, parity, mammogram frequency, palpability, method of presentation, lesion size, hormone receptor status, comedo histology, and recurrence did not differ significantly between the two groups (Table 1). The median follow-up period was 7.1 years.

CONCLUSION

Women with pure DCIS and higher MBD are more likely to be younger at the time of diagnosis, premenopausal, and Asian, and to present with higher-grade disease. Further research on the relationship of age, MBD, and tumor biology in DCIS is warranted.

Specialized dendritic cells induce tumor-promoting IL-10+IL-17+ FoxP3neg regulatory CD4+ T cells in pancreatic carcinoma

The drivers and the specification of CD4+ T cell differentiation in the tumor microenvironment and their contributions to tumor immunity or tolerance are incompletely understood. Using models of pancreatic ductal adenocarcinoma (PDA), we show that a distinct subset of tumor-infiltrating dendritic cells (DC) promotes PDA growth by directing a unique TH-program. Specifically, CD11b+CD103- DC predominate in PDA, express high IL-23 and TGF-β, and induce FoxP3neg tumor-promoting IL-10+IL-17+IFNγ+ regulatory CD4+ T cells. The balance between this distinctive TH program and canonical FoxP3+ TREGS is unaffected by pattern recognition receptor ligation and is modulated by DC expression of retinoic acid. This TH-signature is mimicked in human PDA where it is associated with immune-tolerance and diminished patient survival. Our data suggest that CD11b+CD103- DC promote CD4+ T cell tolerance in PDA which may underscore its resistance to immunotherapy.

Targeting SYK signaling in myeloid cells protects against liver fibrosis and hepatocarcinogenesis

Liver fibrosis and fibrosis-associated hepatocarcinogenesis are driven by chronic inflammation and are leading causes of morbidity and death worldwide. SYK signaling regulates critical processes in innate and adaptive immunity, as well as parenchymal cells. We discovered high SYK expression in the parenchymal hepatocyte, hepatic stellate cell (HSC), and the inflammatory compartments in the fibrotic liver. We postulated that targeting SYK would mitigate hepatic fibrosis and oncogenic progression. We found that inhibition of SYK with the selective small molecule inhibitors Piceatannol and PRT062607 markedly protected against toxin-induced hepatic fibrosis, associated hepatocellular injury and intra-hepatic inflammation, and hepatocarcinogenesis. SYK inhibition resulted in increased intra-tumoral expression of the p16 and p53 but decreased expression of Bcl-xL and SMAD4. Further, hepatic expression of genes regulating angiogenesis, apoptosis, cell cycle regulation, and cellular senescence were affected by targeting SYK. We found that SYK inhibition mitigated both HSC trans-differentiation and acquisition of an inflammatory phenotype in T cells, B cells, and myeloid cells. However, in vivo experiments employing selective targeted deletion of SYK indicated that only SYK deletion in the myeloid compartment was sufficient to confer protection against fibrogenic progression. Targeting SYK promoted myeloid cell differentiation into hepato-protective TNFα^low CD206^hi phenotype downregulating mTOR, IL-8 signaling and oxidative phosphorylation. Collectively, these data suggest that SYK is an attractive target for experimental therapeutics in treating hepatic fibrosis and oncogenesis.

RIP1 Kinase Drives Macrophage-Mediated Adaptive Immune Tolerance in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDA) is characterized by immune tolerance and immunotherapeutic resistance. We discovered upregulation of receptor-interacting serine/threonine protein kinase 1 (RIP1) in tumor-associated macrophages (TAMs) in PDA. To study its role in oncogenic progression, we developed a selective small-molecule RIP1 inhibitor with high in vivo exposure. Targeting RIP1 reprogrammed TAMs toward an MHCII^hiTNFα⁺IFNγ⁺ immunogenic phenotype in a STAT1-dependent manner. RIP1 inhibition in TAMs resulted in cytotoxic T cell activation and T helper cell differentiation toward a mixed Th1/Th17 phenotype, leading to tumor immunity in mice and in organotypic models of human PDA. Targeting RIP1 synergized with PD1-and inducible co-stimulator-based immunotherapies. Tumor-promoting effects of RIP1 were independent of its co-association with RIP3. Collectively, our work describes RIP1 as a checkpoint kinase governing tumor immunity.

The Pancreatic Cancer Microbiome Promotes Oncogenesis by Induction of Innate and Adaptive Immune Suppression

We found that the cancerous pancreas harbors a markedly more abundant microbiome compared with normal pancreas in both mice and humans, and select bacteria are differentially increased in the tumorous pancreas compared with gut. Ablation of the microbiome protects against preinvasive and invasive pancreatic ductal adenocarcinoma (PDA), whereas transfer of bacteria from PDA-bearing hosts, but not controls, reverses tumor protection. Bacterial ablation was associated with immunogenic reprogramming of the PDA tumor microenvironment, including a reduction in myeloid-derived suppressor cells and an increase in M1 macrophage differentiation, promoting TH1 differentiation of CD4⁺ T cells and CD8⁺ T-cell activation. Bacterial ablation also enabled efficacy for checkpoint-targeted immunotherapy by upregulating PD-1 expression. Mechanistically, the PDA microbiome generated a tolerogenic immune program by differentially activating select Toll-like receptors in monocytic cells. These data suggest that endogenous microbiota promote the crippling immune-suppression characteristic of PDA and that the microbiome has potential as a therapeutic target in the modulation of disease progression.Significance: We found that a distinct and abundant microbiome drives suppressive monocytic cellular differentiation in pancreatic cancer via selective Toll-like receptor ligation leading to T-cell anergy. Targeting the microbiome protects against oncogenesis, reverses intratumoral immune tolerance, and enables efficacy for checkpoint-based immunotherapy. These data have implications for understanding immune suppression in pancreatic cancer and its reversal in the clinic. Cancer Discov; 8(4); 403-16. ©2018 AACR.See related commentary by Riquelme et al., p. 386This article is highlighted in the In This Issue feature, p. 371.

Trunk muscle activation characteristics in patients with severe haemophilia

INTRODUCTION

Recurrent bleeding episodes in patients with haemophilia (PWH) lead to joint alterations and therewith disturbed muscle coordination patterns. Major weight-bearing joints are affected most. However, possible effects on trunk muscle activity have not been examined so far. The objective of this work was to study consequences of haemarthropathy on characteristics of trunk muscles in PWH while standing on surfaces with different mechanical properties.

METHODS

Surface EMG of internal oblique (IO) and multifidus (MF) muscles were bilaterally recorded during a natural bilateral stance in 20 PWH with severe haemophilia A [age: 42 years (SD: 10)] and 25 non-haemophilic controls [NHC, 43 (12)]. Amplitude ratios, a symmetry index between sides and the co-activation ratio of IO over MF served as outcome measures and compared standing on three different surfaces (stable, soft, unsteady).

RESULTS

PWH revealed markedly restricted lower extremity joints (P < 0.001), but without any hint of back pain. Neither result revealed significant main or interaction effects of 'group' (P > 0.24). Group-independent analyses showed amplitude ratios (MF: P < 0.05) as well as symmetry indices (MF: P < 0.02) significantly altered by 'surface' in NHC only. Effects of utilizing soft vs. unsteady surfaces were not detectable (P > 0.77).

CONCLUSION

Utilizing unstable surfaces does not lead to altered trunk muscle activity in PWH. Differently than expected, a quite similar behaviour of lower trunk muscles in terms of applied indices can be found in PWH and NHC. Ascending alterations of muscle coordination in PWH could not be verified.

[Interdisciplinary Assessment Criteria for Rehabilitation after Injuries of the Lower Extremity: A Function-Based Return to Activity Algorithm]

BACKGROUND

In the treatment of patients with lower extremity injuries, a paradigm shift is taking place: Time-dependent concepts are increasingly being replaced by function-based concepts.

METHODS

A function-based Return to Activity Algorithm is presented which contains a level classification (I-IV). Qualitative and subsequent quantitative tests are assigned to every level. Within each level, first the respective qualitative test has to be passed before patients are allowed to perform the corresponding quantitative test. Criteria for success are qualitative and quantitative comparisons with the unaffected side. Before entering the next level, both tests have to be successfully passed. The levels are ordered according to increasing demands on the loco-motor system. These demands are adequate stability without impact interaction in sagittal plane for level I, followed by dynamic stability demands for level II. Impacts in frontal plane are added for level III and finally multidirectional impacts have to be compensated at level IV. The time expenditure per level is no more than five minutes. The case of a professional soccer player will serve to exemplify the Return to Activity Algorithm. Following a knee injury, he underwent arthroscopy with ACL reconstruction (patellar tendon) and a partial meniscectomy (lateral and medial).

RESULTS

The athlete was able to successfully pass each level and finished his rehabilitation 203 days post injury. He returned to the team training 221 days post injury. 247 days post injury, the athlete completed his first game.

CONCLUSION

The Return to Activity Algorithm is able to support the evaluation of the functional status of the loco-motor system after injury or surgery and is furthermore capable of uncovering deficits or asymmetries, which are a proven risk for re-injury. This function-oriented individual approach is able to adequately dose the therapeutic efforts on an individual basis. With this approach, the right timing for a safe return to sports activities can be detected with high certainty.

Fabrication and characterization of an electrically contacted vapor cell

We demonstrate the use of electrically contacted vapor cells to switch the transmission of a probe laser. The excitation scheme makes use of electromagnetically induced transparency involving a Rydberg state. The cell fabrication technique involves thin-film-based electric feedthroughs, which are well suited for scaling this concept to many addressable pixels like in flat panel displays.

Ankle muscle activation in people with haemophilia

Since normative surface EMG (SEMG) values for muscles acting at the knee joint are available for people with haemophilia, increasing interest is noticeable for other joints affected by haemophilic arthropathy. Adequate activity of shank muscles is an important key for appropriate postural control. The aim of this study was to determine differences in muscle activation patterns of lower leg muscles between people with and without haemophilia during upright standing. SEMG of tibialis anterior (TA), fibularis longus (FL), lateral (LG) and medial (MG) heads of gastrocnemius, and soleus (SO) muscles of both sides were recorded in 25 haemophilic patients (H) and 25 non-haemophilic control subjects (C) while standing on even ground. The Gilbert-Score was used to assign sides to major (H-MA) and minor (H-MI) affected ankle joints in H. To normalize the SEMG amplitudes, amplitude ratios (percentage of cumulated activity) were calculated. Compared to controls, TA ratios showed higher and MG reduced levels in both H groups (P < 0.01). In the H-MA subgroup of H, FL also joined the TA behaviour whereas SO had similar activation direction as MG. Although possible descending influences from the knee joints cannot be excluded, this can be interpreted as a compensational mechanism due to the severity of the orthopaedic status of the ankle, which with increasing heaviness is accompanied by reduced plantar flexion capability. However, ankle joint integrity appears to be reduced in H, with TA and MG seeming to play key roles for neuromuscular control of upright posture.

FK506 prevents stroke-induced generation of ceramide and apoptosis signaling

Ceramide is a key mediator of apoptosis during the cellular stress response which is also involved in stroke-induced death. Transient occlusion of the middle cerebral artery (MCA) in rats led to a strong generation of ceramide as measured in thalamus and entorhinal cortex of the ischemic brain tissue. Enhanced levels of ceramide may be involved in apoptosis signaling following stroke since exogenously added synthetic C2-ceramide increased expression of c-jun and the death-inducing ligands (DILs) CD95-L, TRAIL and TNF-alpha in neuroblastoma cells. DILs in turn mediated death via binding to their respective receptors as concluded from diminished apoptosis upon blocking of the common pathway by dominant negative FADD. C2-ceramide induced both necrosis and apoptosis in a concentration-dependent manner corresponding to the situation present in the ischemic brain. The immunosuppressant FK506 inhibited the release of ceramide, expression of CD95-L and apoptosis in an in vitro and in vivo model for ischemia/reperfusion. These data suggest that ceramide is a crucial initiator of death, e.g., by induction of DILs following stroke.

Spinalin, a new glycine- and histidine-rich protein in spines of Hydra nematocysts

Here we present the cloning, expression and immunocytochemical localization of a novel 24 kDa protein, designated spinalin, which is present in the spines and operculum of Hydra nematocysts. Spinalin cDNA clones were identified by in situ hybridization to differentiating nematocytes. Sequencing of a full-length clone revealed the presence of an N-terminal signal peptide, suggesting that the mature protein is sorted via the endoplasmic reticulum to the post-Golgi vacuole in which the nematocyst is formed. The N-terminal region of spinalin (154 residues) is very rich in glycines (48 residues) and histidines (33 residues). A central region of 35 residues contains 19 glycines, occurring mainly as pairs. For both regions a polyglycine-like structure is likely and this may be stabilized by hydrogen bond-mediated chain association. Similar sequences found in loricrins, cytokeratins and avian keratins are postulated to participate in formation of supramolecular structures. Spinalin is terminated by a basic region (6 lysines out of 15 residues) and an acidic region (9 glutamates and 9 aspartates out of 32 residues). Western blot analysis with a polyclonal antibody generated against a recombinant 19 kDa fragment of spinalin showed that spinalin is localized in nematocysts. Following dissociation of the nematocyst's capsule wall with DTT, spinalin was found in the insoluble fraction containing spines and the operculum. Immunocytochemical analysis of developing nematocysts revealed that spinalin first appears in the matrix but then is transferred through the capsule wall at the end of morphogenesis to form spines on the external surface of the inverted tubule and the operculum.

CD95 (APO-1/Fas) mutations in childhood T-lineage acute lymphoblastic leukemia

CD95 (APO-1/Fas)-mediated apoptosis is pivotal in normal lymphocyte homeostasis and mutations of CD95 cause a benign autoimmune lymphoproliferation syndrome (ALPS) in humans and mice. However, tumors only rarely develop in these patients, and no CD95 mutations have yet been directly implicated in tumorigenesis. We therefore examined 81 de novo childhood T-lineage acute lymphoblastic leukemias (T-ALL) including 54 steroid-poor responders, 10 relapsed T-ALL, and 10 leukemic T-cell lines, for the presence of CD95 mutations using single-strand confirmation polymorphism and sequence analysis. In leukemic blasts and normal T cells of one patient, a heterozygous mutation in exon 3 of CD95 causing a 68Pro --> 68Leu change associated with decreased CD95-mediated apoptosis was found. In leukemic blasts and normal T cells of a second patient, a homozygous mutation in the promoter of CD95 causing disruption of a consensus sequence for AP-2 binding without decreasing constitutive CD95 expression was detected. No large intragenic alterations of CD95 were found, no homozygous loss was detected in the cell lines, and no CD95 mutations were detected in the relapses. The data presented here show that CD95 mutations occur in some T-ALL and may be of biological importance.

An unexpected pathway for the metabolic degradation of 1,3-dialkyl-3-acyltriazenes

In the presence of NADPH, rat liver microsomes catalyzed the degradation of a series of 1,3-dialkyl-3-acyltriazenes, and the extent of the reaction was correlated with compound lipophilicity. In the case of two methylcarbamoyltriazenes, 1-(2-chloroethyl)-3-benzyl-3- (methylcarbamoyl)triazene (CBzM) and 1-(2-chloroethyl)-3-methyl-3-(methylcarbamoyl)triazene (CMM), microsomal metabolites were isolated. Identification of the CBzM metabolites as 1-(2-chloroethyl)-3-benzyl-3-(hydroxymethylcarbamoyl)triazene and 1-(2-chloroethyl-3-benzyl-3-carbamoyltriazine, and the CMM metabolite as 1-(2-chloroethyl)-3-methyl-3-(hydroxymethylcarbamoyl)triazene indicated that the first metabolic step involves hydroxylation of the methylcarbamoyl substituent. Detailed studies of the metabolism of CBzM indicated that the Km for the reaction was 84 microM, and that metabolism was more efficient if microsomes were prepared from male than from female rats. During prolonged incubation, the metabolites of CBzM were also degraded. The degradation of CBzM and its metabolites was inhibited by SKF-525A and metyrapone, suggesting the involvement of a cytochrome P450 isozyme, and supporting the hypothesis that the process is oxidative rather than hydrolytic in both cases. Metabolic oxidation represents an alternative pathway to chemical or enzymatic hydrolysis for the in vivo decomposition of (methylcarbamoyl)triazenes. This mechanism may ultimately explain the antitumor efficacy and low acute toxicity of selected compounds.

The primitive metazoan Hydra expresses antistasin, a serine protease inhibitor of vertebrate blood coagulation: cDNA cloning, cellular localisation and developmental regulation

We have isolated and characterized cDNAs from Hydra which encode antistasin, a potent inhibitor of factor Xa in the vertebrate blood clotting cascade. Hydra antistasin is expressed in gland cells and represents a major class of transcripts from Hydra's head. Sequence analysis revealed that Hydra antistasin contains 6 internal repeats of a 25-26 amino acid sequence with a highly conserved pattern of 6 cysteine and 2 glycine residues identical to that in leech antistasin. Conservation of antistasin in a lower metazoan provides a potential link between the vertebrate and invertebrate coagulation systems.

[Acute generalized pustulosis. A clinico-histopathological study on differential diagnosis (author's transl)]

Case report of a 51 years old woman with an acute generalized pustulosis. The histopathological findings in the epidermis were those of pustular psoriasis. But vascular findings in the corium were suggestive of a drug reaction, as was the history of a drug-induced onset of the disease in the course of an infect of the upper respiratory tract. Thus exanthematic pustular psoriasis may be considered as both diseases, psoriasis and drug reaction.

[Dose reduction in xeromammography (author's transl)]

The use of a total filter of 3 mm of aluminium permits a considerable reduction of the radiation dose in xeromammography using the senographe. In comparison with conventional xeroradiography radiation is reduced by a factor of 2 to 3, in comparison with foilless film by a factor of 10 to 12. The applied tissue dose is between 0.14 and 0.30 rad per exposure. The presently still hypothetic radiogenic risk of carcinoma due to mammography is thus lower for this system than with other systems. The quality of the radiograph and the diagnostic validity are not reduced by this technique.

[Duct pattern of the breast. An indicator of patients with increased risk of breast cancer development? A histological and mammographic study with 160 cases of breast cancer (author's transl)]

In 1975 John Wolfe proposed a classification of mammographic findings concerning the distribution of the duct pattern to select patients with high cancer risk. In a retrospective study we classified 160 patients with breast cancer according to the duct pattern classification. Our findings support well the results of Wolfe. Type N (normal duct pattern) is found in only 8,9% of all cancer patients whereas breast cancer was combined in 80% with the P2-DY-type. Our investigation confirms the classification of the duct pattern according to Wolfe as a valuable addition to the mammographic diagnosis of breast cancer.

[The therapy of the hypertensive form of late gestosis (author's transl)]

Based on five cases of intrauterine death associated with preeclamptic toxemia, a possible relationship between the antihypertensive treatment with Catapres and the fatal outcome of the fetus is discussed. Catapres is known to decrease cardiac output and, in addition, diminishes the utero-placental circulation. For effective prevention of hemodynamic failure in such cases, it is advisable to use Catapres only in combination with adequate intravenous infusion therapy. Further investigations concerning this possible relationship should be done to determine sufficiently whether or not Catapres can be used without risk as a hypertensive drug in late gestosis.

[Value of different systems of mammography records with regard to their exposure to radiation and their information content (author's transl)]

We learned from our examinations that, if there were optimum conditions, the combination Medichrome MR50 as a form of low dose method offers the same information content as the film without intensifying screens PE 4006. We found out that the discernibleness of details of 70 non selected mammographies which had each been taken by both systems was absolutely identical. By xeroradiography, however, a more precise representation of details, especially if there are microcalcifications, is possible because of its effect which renders the edges more visible. If the Medichrome low dose method was applied, the exposure to radiation of the breast was, depending on the density and width or the organ, only 1/12 to 1/14 of the dose measured if the film without intensifying screens was used. The exposure to radiation connected with xeroradiography is between these two values. We came to the following conclusion: the low dose method is recommended for routine mammographies, and only if there are special problems or if suspicious findings are to be clarified, xeroradiography is applied as supplementary examination method. Before using the film without intensifying screens, one should consider the high radiation exposure which, however, does not involve a greater information content.

[Changes in the blood rheology and their influence on the oxygen diffusion in normal and pathological pregnancies (author's transl)]

Blood viscosity studies were carried out at regular intervals in 51 patients with normal pregnancy and in 27 patients with high risk pregnancy, i.e. with EPH-gestosis and placental insufficiency. During gestation the relative blood viscosity is significantly increased compared to 15 normal non-pregnant women. At a corrected hematocrit of 45% we found a direct correlation to plasma fibrinogen and to the blood sedimentation rate. Although the whole blood viscosity does not indicate any change in normal pregnant women, there is, however, a viscosity increase in the last trimester of high risk pregnancies. Additionally a mathematical model of the oxygen diffusion in the placental cotyledo demonstrates rapid decrease of the oxygen partial pressure in the maternal intervillous channel if the microcirculation of the "Placenton" is impaired.

[A simple filtration technique for the observation of the deformation of human erythrocytes during pregnancy (author's transl)]

A simple rheological test method, as developed by Reid and Dormandy, was applied. In a group of pregnant women (n = 25) without pathological conditions the filtrability of whole blood and of a 10% erythrocyte suspension was determined. The control is a group of healthy nonpregnant patients (n = 7) at different times of the ovulatory cycle. Compared with the control group the flow rate of whole blood in the pregnant state is decreased about 30%, whereas that of the erythrocyte suspension about 40%.

[Trace-element concentration in the human placenta in a strong contaminated environment (author's transl)]

By means of NAA the content of trace elements in human placentae from a strong contaminated environment (Essen) was determinated and compared with former results from Bavaria. The data show highly significant elevation of the concentration of Cd, Cr, La and Br in Essen, which counts for the industrial waste of this region. In contrast the element As is highly increased in placentae from the rural Bavarian districts. This may be caused by the wide spread application of plant protective insecticides in the past.